Reactions of Cisplatin with Thioredoxin-1 Regulate Intracellular Redox Homeostasis.

Cisplatin is a widely used anticancer drug. In addition to inducing DNA damage, increased levels of reactive oxygen species (ROS) play a significant role in cisplatin-induced cell death. Thioredoxin-1 (Trx1), a redox regulatory protein that can scavenge ROS, has been found to eliminate cisplatin-induced ROS, while elevated Trx1 levels are associated with cisplatin resistance. However, it is unknown whether the effect of Trx1 on the cellular response to cisplatin is due to its direct reaction and how this reaction influences the activity of Trx1. In this work, we performed detailed studies of the reaction between Trx1 and cisplatin. Trx1 is highly reactive to cisplatin, and the catalytic motif of Trx1 (CGPC) is the primary binding site of cisplatin. Trx1 can bind up to 6 platinum moieties, resulting in the structural alteration and oligomerization of Trx1 depending on the degree of platination. Platination of Trx1 inhibits its interaction with ASK1, a Trx1-binding protein that regulates cell apoptosis. Furthermore, the reaction with cisplatin suppresses drug-induced ROS generation, which could be associated with drug resistance. This study provides more insight into the mechanism of action of cisplatin.

Cranioplasty Using Polymethylmethacrylate Cement Following Retrosigmoid Craniectomy Decreases the Rate of Cerebrospinal Fluid Leak and Pseudomeningocele.

OBJECTIVE: Cerebrospinal fluid (CSF) leak frequently occurs after retrosigmoid craniectomy. The present study investigated the effects of cranioplasty using polymethylmethacrylate (PMMA) cement to reduce the incidence of CSF leak following retrosigmoid craniectomy as compared with the autologous bone flap combined with titanium plates. METHODS: Two hundred forty-three patients underwent surgeries via retrosigmoid approach for microvascular decompression or tumor resection. Of these, 107 patients underwent craniotomy, and incomplete cranioplasty was performed with autologous bone flap fixed with titanium plates, while 136 patients underwent craniectomy and complete cranioplasty was performed with PMMA cement. Variables including the incidence of CSF leak, pseudomeningocele formation, wound infection, rejection reaction were compared retrospectively based on the clinical data between the 2 groups. RESULTS: In the autologous bone group, 9 patients had postoperative CSF leaks, and 11 patients had pseudomeningoceles, while 3 CSF leaks and 2 pseudomeningoceles were found in the PMMA group. Statistical analysis showed that PMMA significantly decreased the incidence of postoperative CSF leaks (P = 0.03) and pseudomeningocele formation (P = 0.002). Wound infections were observed in 2 and 1 patients between the autologous bone and PMMA group, respectively, which did not differ significantly (P = 0.58). None of the patients in both groups developed a rejection reaction of artificial materials. CONCLUSIONS: Complete cranioplasty with PMMA cement following retrosigmoid craniectomy could decrease the incidence of CSF leak and pseudomeningocele formation as compared with the autologous bone flap combined with titanium plates. Thus, PMMA cement is preferable for bone reconstruction with excellent biocompatibility and without increasing the rate of wound infection.

[Microvascular decompression for hemifacial spasm induced by vertebral artery dissecting aneurysm: one case report].

A 61-year-old female presented with 4 years history of left-sided hemifacial spasm. Head MRI and angiography indicated left vertebral artery dissecting aneurysm which compressed ipsilateral cranial nerves Ⅶ and Ⅷ. Microvascular decompression was performed. The dissecting aneurysm was pushed apart and the distal part of the parent artery was adhered to the dura on the petrosum. The compressed nerves were totally decompressed. The symptom of facial spasm was completely resolved immediately after surgery and did not recur during 6 months of follow up.

Preoperative evaluation of neurovascular relationships for microvascular decompression: Visualization using Brainvis in patients with idiopathic trigeminal neuralgia.

OBJECTIVE: A precise and accurate evaluation of neurovascular relationships in patients with idiopathic trigeminal neuralgia (ITN) scheduled for microvascular decompression is necessary. Thus, we constructed and evaluated a fusion imaging technique combining multi-source heterogeneous imaging data from three-dimensional magnetic resonance (MR) and computerized tomography venoangiography (CTV), which enabled use of virtual reality to preoperatively assess the neurovascular relationships, in patients with ITN scheduled for microvascular decompression. METHODS: A single-center observational study. In total, eight patients with ITN scheduled for microvascular decompression were included. Patients underwent three-dimensional MR imaging with time-of-flight (TOF) and fast imaging employing steady state acquisition (FIESTA) sequences and CTV before microvascular decompression. A fusion imaging technique, combining MR-TOF, MR-FIESTA, and CTV images, was used to construct a three-dimensional model with information regarding the facial and auditory nerves, brain tissue, skull, arteries and veins. The positions of the trigeminal nerve and the responsible vessels were observed. The agreement between intraoperative neurovascular compression findings and preoperative evaluation results, and the duration required to determine the neurovascular relationships, were evaluated. RESULTS: The neurovascular relationships as determined with the fusion imaging technique were consistent with intraoperative neurovascular compression findings in all patients. Moreover, the assessment duration was significantly shorter with the fusion imaging technique than with the three-dimensional MR (P<0.05). The rate of an accurate assessment was significantly higher with the fusion imaging technique than with three-dimensional MR (P<0.05). CONCLUSIONS: The fusion imaging technique is a useful tool for the diagnosis and decision-making process based on neurovascular relationships in patients with ITN scheduled for microvascular decompression.

Trigeminal neuralgia associated with cerebellar pial arteriovenous fistula: A case report.

RATIONALE: Trigeminal neuralgia (TN) is frequently associated with compression at the root entry zone of the trigeminal nerve by an aberrant loop of an artery, tributaries of the petrosal vein, tumors, aneurysm, and vascular malformation. TN associated with a cerebellar pial arteriovenous fistula (PAVF) has not been described previously. PATIENT CONCERNS: A 65-year-old man presented with right-sided TN. Cerebral angiography revealed a right cerebellar PAVF and magnetic resonance imaging demonstrated a mixed compression of the petrous vein complex and anterior inferior cerebellar artery at the right trigeminal nerve. DIAGNOSIS: Due to the patient's symptoms, radiographic findings, he was diagnosed with TN and PAVF. INTERVENTIONS: Coiling combined with use of the liquid embolic agent Onyx was used for the complete embolization of the fistula. OUTCOMES: Complete relief of the pain was achieved 3 months after endovascular treatment, and the patient has remained pain-free during 2 years of follow-up. CONCLUSIONS: Endovascular treatment with a combination of coils and Onyx embolization is an effective approach for complete resolution of rarely occurring TN caused by mixed venous and arterial compressions associated with cerebellar PAVF.

A multivariate analysis of the prognostic factors of grade III gliomas.

BACKGROUND: Glioma is the most common type of malignant brain tumor and the prognosis of glioma is still poor. Moreover, the prognosis of patients diagnosed with grade III gliomas varies significantly. In this study, we assessed the factors that contribute to the prognosis of patients with grade III gliomas. METHODS: Data from 97 patients with grade III glioma who received surgery from 2000 to 2005 were included in this study. Kaplan-Meier survival analysis and Cox regression analysis were used to analyze the prognostic effects of 16 different factors selected from clinical characteristics, results from neuroimaging and pathological examinations, as well as different treatment schemes. RESULTS: The results indicated that age, preoperative Karnofsky Performance Scale score, extent of tumor invasion, tumor resection degree, residual tumor shown by postoperative magnetic resonance imaging (MRI), and postoperative radiotherapy and chemotherapy all correlated with patient prognosis. Furthermore, Cox multivariate analysis also showed the age (P < 0.01), extent of tumor invasion (P < 0.01), residual tumor shown by postoperative MRI (P < 0.05), and postoperative radiotherapy (P < 0.05) significantly correlated with patients' prognosis. CONCLUSIONS: Age, postoperative radiotherapy and residual tumor indicated by MRI after surgery correlated significantly with the prognosis of patients with grade III glioma. The extent of tumor invasion may be an independent prognostic factor for patients with grade III glioma.